Magnetic core

About: Magnetic core is a research topic. Over the lifetime, 30011 publications have been published within this topic receiving 155247 citations.

Low-profile transformer and method of manufacturing the transformer

Abstract: A low-profile transformer for switching power supply, wherein insulating paper (13) having at least one of pressure sensitive adhesive and adhesive agent on both surfaces is inserted between low-profile coil layers at at least one position to form a multi-layer coil, and magnetic cores (15) are assembled from the upper and lower sides of the multi-layer coil, whereby a variation in distances between upper and lower coils (11) and coils (12) and distances between the coils (11) and (12) and the magnetic core (15) can be suppressed.

A test case for validation of magnetic field analysis with vector hysteresis

Abstract: An experimental setup, made up of a three-limbed ferromagnetic core fitted with pickup coils, has been designed and built to be used as test bench for validation of magnetic field analysis with hysteresis. Unidirectional or rotational flux patterns and distorted waveforms can be generated by modifying the supply conditions of the coils. A detailed description of the structure with its supply and pickup coils is given. The analysis has been developed under different operating conditions. The experimental results of local and integral quantities are presented and compared with finite-element methods simulations.

The effect of flux diverters on AC losses of a 10 kVA high temperature superconducting demonstrator transformer

Abstract: In this paper the design, construction and characterization of a 50 Hz single phase high temperature superconducting (HTS) transformer is presented. The transformer is designed to deliver 10 kVA at 77.4 K and 20 kVA at 65 K. The transformer is made of two windings positioned at the middle limb of a three-limb iron core. The secondary winding is made of nine double pancake superconducting coils, using silver sheathed BPSCCO-2223 multifilamentary tapes with nominal critical current of 20 A (at 77.4 K and self field). The primary winding is made of copper to reduce the cost of HTS material. Utilizing a superinsulated nonmetallic doughnut shaped cryostat with low background heat leak, the AC losses in the superconducting winding have been measured by calorimetric method. Two powdered iron flux diverters have been used inside the cryostat at both ends of the superconducting winding in order to reduce the radial component of leakage flux density in the HTS tapes. The use of these flux diverters is shown to be very effective in reducing the AC losses by 40% at the nominal current.

Electrically-variable inductor

Abstract: An inductive device includes a principal magnetic core (11) having a principal winding (10) coupled therewith so that the reluctance of the principal core influences the inductance of the principal winding. A control winding (12) is coupled to a control magnetic core (13) so that the current in the control winding influences the magnetic flux in the control core. The control core intersects the principal core so that magnetic flux produced in the control core interferes with the principal core. Selective control of current in the control winding influences the magnetic flux in the control core, which in turn interferes with the principal core so as to influence the reluctance thereof and thereby vary the inductance of the principal winding. Additional control windings may be coupled to respective additional control cores (13a, 13b, 13c) which intersect the principal core, so that selective control of the currents in the various control windings enables selective control of the degree of interference with the principal core, and hence the reluctance thereof. The dimensions of respective reluctance control regions where the control cores intersect the principal core may be selected such that the degrees of influence of the individual control cores are in a binary sequence.

Design and Realization of a Novel Compact Fluxgate Current Sensor

Abstract: A new closed-loop magnetic current sensor is presented in this paper. The sensor consists of two toroidal magnetic cores. One core works in fluxgate principle for the measurement of dc and low-frequency ac, and the other one is used as a current transformer for higher frequency application. Based on the simulation results, a prototype was designed, and the test results have a good agreement with the simulation results. The closed-loop configuration with a magnetic core and a feedback winding in the sensor improved the sensitivity of the sensor, eliminated the offset and drift related to temperature, and greatly reduced the error caused by magnetic hysteresis phenomenon. It can measure currents up to 20 A, with an accuracy of 0.5%, and a 50 kHz small signal bandwidth.